Is Venus the two-faced cat really a chimera?

Genetics explained, with added kittens.

Venus the cat has been in the news. She has heterochromia – that is, her two eyes are different colours – as well as a perfectly placed black splodge (technical term), which makes her look like Popular Batman Villain Two-Face.

Why is she like that? One possibility is that she is a chimera. This term, taken from the mythical monster with the heads of a goat, lion and snake, refers to a real – albeit relatively rare – condition where two genetically distinct embryos merge in the womb.

A chimera is essentially the reverse of identical twins. In the latter, one fertilised egg splits completely and forms two separate embryos; in the former, two fertilised eggs merge together and grow into one child.

The cells which come from each of the fertilised eggs maintain their own character – so if one egg had genes for black hair and the other for white, the resulting chimera would have mottled black and white fur:

A chimeric rat with her babies. Photograph: Wikimedia commons

The thing is, Venus may not actually be a chimera.: her perfectly split face may just be a fluke placement of an otherwise normal tortoiseshell pattern. National Geographic's Katia Andreassi writes:

Female cats, said Leslie Lyons, a professor at the University of California, Davis, already have two X chromosomes so they can sport that coat without the extra X. That means Venus is not necessarily a chimera.

To find out would require genetic testing, said Lyons. With samples of skin from each side of the cat, "we can do a DNA fingerprint—just like on CSI—and the DNA from one side of the body should be different than the other."

But there is still a mystery about Venus - her single blue eye. Andreassi adds:

Cat eyes are typically green or yellow, not blue. A blue-eyed cat is typically a Siamese or else a cat with "a lot of white on them," she explained.

Venus appears to have only a white patch on her chest, which to Lyons is not enough to explain the blue eye.

Science: making cool cats cooler.

Venus the "chimera" cat.

Alex Hern is a technology reporter for the Guardian. He was formerly staff writer at the New Statesman. You should follow Alex on Twitter.

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Why did Julian Assange lose his internet connection?

Rumours of paedophilia have obscured the real reason the WikiLeaks founder has been cut off from the internet. 

In the most newsworthy example of "My house, my rules" this year, Julian Assange's dad (the Ecuadorian embassy in London) has cut off his internet because he's been a bad boy. 

Rumours that the WikiLeaks' founder was WiFi-less were confirmed by Ecuador's foreign ministry late last night, which released a statement saying it has "temporarily restricted access to part of its communications systems in its UK Embassy" where Assange has been granted asylum for the last four years. 

Claims that the embassy disconnected Assange because he had sent sexually explicit messages to an eight-year-old girl —first reported by the US political blog Daily Kos — have been quashed. Wikileaks responded by denying the claims on Twitter, as Ecuador explained the move was taken to prevent Assange's interference with the US election. The decision follows the publication of leaked emails from Hillary Clinton's campaign adviser John Podesta, as well as emails from the Democratic National Committee (DNC), by WikiLeaks.

Ecuador "respects the principle of non-intervention in the internal affairs of other states," read the statement, though the embassy have confirmed they will continue to grant Assange asylum. 

Assange first arrived at the Ecuadorian embassy in London in June 2012, after being sought for questioning in Sweden over an allegation of rape, which he denies. WikiLeaks claims this new accusation is a further attempt to frame Assange.  "An unknown entity posing as an internet dating agency prepared an elaborate plot to falsely claim that Julian Assange received US$1M from the Russian government and a second plot to frame him sexually molesting an eight year old girl," reads a news story on the official site.

It is unclear when Assange will be reconnected, although it will presumably be after the US presidential election on 8 November.

Amelia Tait is a technology and digital culture writer at the New Statesman.